While the consequences of the 479-page tax bill currently under ominous development in D.C. are still being evaluated, some — like the Author’sGuild — already fear it could hurt independent professionals and freelancers come tax time.

Bill or no bill, freelancers need to have their math on point. It’s why Mike Wilner’s startup Compass rolled out a handy tool called the Freelance Project Tax Calculator on Product Hunt Tuesday.

It’s basically a spreadsheet that lets people calculate tax withholding on freelance projects, by entering common freelance project costs and figuring out the right price points to ensure take-home pay is where it should be.

“Understanding the portion of your freelance income that needs to be set aside for taxes is really important,” Wilner said in an email. “Too frequently, freelancers simply collect their money and don’t build these costs into their pricing, and get blindsided when it’s time to pay taxes. We wanted to provide an extremely transparent way for freelancers to be able to see how much of their revenue goes to project costs, taxes, and what they get to take home.”

Over the summer, Compass pivoted to operate as a web development agency and away from the web design marketplace model it initially followed. As part of the shift, the company launched a software product called Sail which promises to help freelancers manage invoicing, a frequent gripe from independent professionals.